The genus _Marara_ was based by Karsten (Linnaea, =28=: 389) on _M. bicuspidata_ from Colombia, a cespitose palm having a trunk 7 meters high and 10 cm. in diameter, clothed with black spines 6 to 8 mm. long. The leaves are 125 cm. long with from 60 to 80 pairs of cuneate pinnules which measure 3 dm. in length and 15 cm. in width, and are clustered in sixes or eights. This appears to be a very extreme development of the leaf-arrangement seen in the cultivated palm commonly called _Martinezia caryotaefolia_ where the leaflets are distinctly clustered, but by no means so crowded as must be the case when on the side of a leaf 125 cm. long are leaflets with an aggregate width of 10–13 m. The palm commonly cultivated in conservatories as _Martinezia caryotaefolia_ is obviously allied to _Curima_, perhaps more closely than to either _Aiphanes_ or _Marara_, but in addition to the clustered pinnules it has a more slender habit, especially apparent in the long internodes and the more lax inflorescence. This difference in habit is also evidently correlated with the fact that the leaf-bases do not become deeply gibbous and obliquely inclined from the trunk as in _Curima_ but remain closely sheathing. Moreover, the upper side of the leaf-stalk which in the Puerto Rico palm is deeply channeled and has lateral corners sharp or torn into fibers nearly to the insertion of the lowest pinnae is in the conservatory species nearly cylindrical for a long distance below the pinnae, and has long spines on the upper side as well as on the lower. It is as though the ligule were located in _Curima_ near the insertion of the lowest pinnae while in the other form it remains close to the trunk, with a cylindrical section intercalated to reach to where the pinnae begin. Apparently we are dealing with still another generic group for which the name =Tilmia= would not be inappropriate in allusion to the shorn and disheveled appearance which it shares with _Curima_. The species studied are =Tilmia caryotaefolia= (_Martinezia caryotaefolia_ H.B.K. Nov. Gen. et Sp. =I=: 305. _pl. 699_) in the National Botanic Garden and =T. disticha= (_Martinezia disticha_ Linden, Cat. 32. 1875). The seeds of _Tilma caryotaefolia_ are like those of _Curima_, but considerably larger, rounder, and much smoother. The foramina are peripheral, but are much smaller and more shallow, those of _Curima_ being surrounded, as it were, by a prominent rim which adds somewhat to the apparent width of the seed. In both genera the nuts are unsymmetrical, the side which has the largest foramen being distinctly larger than the others and in _Curima_ the irregularly pitted sculpture is coarser. ACROCOMIA Martius, Hist. Nat. Palm. =2=: 66